Designed to encourage children to play games using addition, subtraction and division while also helping to develop better hand-eye coordination skills. So much fun children won’t even realize they are learning! Three large target boards showing numbers 10 to 100, 0 to 10 and 0 to 20. The 9 balls stick to the boards using a hook and loop mechanism. Boards measure 45 cm Diam. (17-3/4” Diam.), balls measure 4 cm (1-1/2”) Diam.